This invention relates to an apparatus for correcting a black level of a video signal.
In the field of color television receivers, there are various apparatuses for correcting a color-tone component of a video signal to widen the dynamic range of a reproduced color image and thereby to clarify the reproduced color image. Some of such color-tone correcting apparatuses have a non-linear amplifier for processing a video signal. Black-level correcting apparatuses are of one type of such color-tone correcting apparatuses. As will be explained later, a prior art black-level correcting apparatus has some problem.